
<!DOCTYPE HTML>
<html lang="zh-hans" >
    <head>
        <meta charset="UTF-8">
        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
        <title>基于select的多路复用 · Go语言圣经</title>
        <meta http-equiv="X-UA-Compatible" content="IE=edge" />
        <meta name="description" content="">
        <meta name="generator" content="GitBook 3.2.3">
        
        
        
    
    <link rel="stylesheet" href="../gitbook/style.css">

    
            
                
                <link rel="stylesheet" href="../gitbook/gitbook-plugin-katex/katex.min.css">
                
            
                
                <link rel="stylesheet" href="../gitbook/gitbook-plugin-highlight/website.css">
                
            
                
                <link rel="stylesheet" href="../gitbook/gitbook-plugin-fontsettings/website.css">
                
            
        

    

    
        
    
        
    
        
    
        
    
        
    
        
    

        
    
    
    <meta name="HandheldFriendly" content="true"/>
    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
    <meta name="apple-mobile-web-app-capable" content="yes">
    <meta name="apple-mobile-web-app-status-bar-style" content="black">
    <link rel="apple-touch-icon-precomposed" sizes="152x152" href="../gitbook/images/apple-touch-icon-precomposed-152.png">
    <link rel="shortcut icon" href="../gitbook/images/favicon.ico" type="image/x-icon">

    
    <link rel="next" href="ch8-08.html" />
    
    
    <link rel="prev" href="ch8-06.html" />
    

    </head>
    <body>
        
<div class="book">
    <div class="book-summary">
        
            
            
                <nav role="navigation">
                


<ul class="summary">
    
    

    

    
        
        
    
        <li class="chapter " data-level="1.1" data-path="../">
            
                <a href="../">
            
                    
                    前言
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.1.1" data-path="../ch0/ch0-01.html">
            
                <a href="../ch0/ch0-01.html">
            
                    
                    Go语言起源
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.1.2" data-path="../ch0/ch0-02.html">
            
                <a href="../ch0/ch0-02.html">
            
                    
                    Go语言项目
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.1.3" data-path="../ch0/ch0-03.html">
            
                <a href="../ch0/ch0-03.html">
            
                    
                    本书的组织
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.1.4" data-path="../ch0/ch0-04.html">
            
                <a href="../ch0/ch0-04.html">
            
                    
                    更多的信息
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.1.5" data-path="../ch0/ch0-05.html">
            
                <a href="../ch0/ch0-05.html">
            
                    
                    致谢
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.2" data-path="../ch1/ch1.html">
            
                <a href="../ch1/ch1.html">
            
                    
                    入门
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.2.1" data-path="../ch1/ch1-01.html">
            
                <a href="../ch1/ch1-01.html">
            
                    
                    Hello, World
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.2" data-path="../ch1/ch1-02.html">
            
                <a href="../ch1/ch1-02.html">
            
                    
                    命令行参数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.3" data-path="../ch1/ch1-03.html">
            
                <a href="../ch1/ch1-03.html">
            
                    
                    查找重复的行
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.4" data-path="../ch1/ch1-04.html">
            
                <a href="../ch1/ch1-04.html">
            
                    
                    GIF动画
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.5" data-path="../ch1/ch1-05.html">
            
                <a href="../ch1/ch1-05.html">
            
                    
                    获取URL
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.6" data-path="../ch1/ch1-06.html">
            
                <a href="../ch1/ch1-06.html">
            
                    
                    并发获取多个URL
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.7" data-path="../ch1/ch1-07.html">
            
                <a href="../ch1/ch1-07.html">
            
                    
                    Web服务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.8" data-path="../ch1/ch1-08.html">
            
                <a href="../ch1/ch1-08.html">
            
                    
                    本章要点
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.3" data-path="../ch2/ch2.html">
            
                <a href="../ch2/ch2.html">
            
                    
                    程序结构
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.3.1" data-path="../ch2/ch2-01.html">
            
                <a href="../ch2/ch2-01.html">
            
                    
                    命名
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.2" data-path="../ch2/ch2-02.html">
            
                <a href="../ch2/ch2-02.html">
            
                    
                    声明
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.3" data-path="../ch2/ch2-03.html">
            
                <a href="../ch2/ch2-03.html">
            
                    
                    变量
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.4" data-path="../ch2/ch2-04.html">
            
                <a href="../ch2/ch2-04.html">
            
                    
                    赋值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.5" data-path="../ch2/ch2-05.html">
            
                <a href="../ch2/ch2-05.html">
            
                    
                    类型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.6" data-path="../ch2/ch2-06.html">
            
                <a href="../ch2/ch2-06.html">
            
                    
                    包和文件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.7" data-path="../ch2/ch2-07.html">
            
                <a href="../ch2/ch2-07.html">
            
                    
                    作用域
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.4" data-path="../ch3/ch3.html">
            
                <a href="../ch3/ch3.html">
            
                    
                    基础数据类型
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.4.1" data-path="../ch3/ch3-01.html">
            
                <a href="../ch3/ch3-01.html">
            
                    
                    整型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.4.2" data-path="../ch3/ch3-02.html">
            
                <a href="../ch3/ch3-02.html">
            
                    
                    浮点数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.4.3" data-path="../ch3/ch3-03.html">
            
                <a href="../ch3/ch3-03.html">
            
                    
                    复数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.4.4" data-path="../ch3/ch3-04.html">
            
                <a href="../ch3/ch3-04.html">
            
                    
                    布尔型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.4.5" data-path="../ch3/ch3-05.html">
            
                <a href="../ch3/ch3-05.html">
            
                    
                    字符串
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.4.6" data-path="../ch3/ch3-06.html">
            
                <a href="../ch3/ch3-06.html">
            
                    
                    常量
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.5" data-path="../ch4/ch4.html">
            
                <a href="../ch4/ch4.html">
            
                    
                    复合数据类型
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.5.1" data-path="../ch4/ch4-01.html">
            
                <a href="../ch4/ch4-01.html">
            
                    
                    数组
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.5.2" data-path="../ch4/ch4-02.html">
            
                <a href="../ch4/ch4-02.html">
            
                    
                    Slice
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.5.3" data-path="../ch4/ch4-03.html">
            
                <a href="../ch4/ch4-03.html">
            
                    
                    Map
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.5.4" data-path="../ch4/ch4-04.html">
            
                <a href="../ch4/ch4-04.html">
            
                    
                    结构体
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.5.5" data-path="../ch4/ch4-05.html">
            
                <a href="../ch4/ch4-05.html">
            
                    
                    JSON
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.5.6" data-path="../ch4/ch4-06.html">
            
                <a href="../ch4/ch4-06.html">
            
                    
                    文本和HTML模板
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.6" data-path="../ch5/ch5.html">
            
                <a href="../ch5/ch5.html">
            
                    
                    函数
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.6.1" data-path="../ch5/ch5-01.html">
            
                <a href="../ch5/ch5-01.html">
            
                    
                    函数声明
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.2" data-path="../ch5/ch5-02.html">
            
                <a href="../ch5/ch5-02.html">
            
                    
                    递归
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.3" data-path="../ch5/ch5-03.html">
            
                <a href="../ch5/ch5-03.html">
            
                    
                    多返回值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.4" data-path="../ch5/ch5-04.html">
            
                <a href="../ch5/ch5-04.html">
            
                    
                    错误
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.5" data-path="../ch5/ch5-05.html">
            
                <a href="../ch5/ch5-05.html">
            
                    
                    函数值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.6" data-path="../ch5/ch5-06.html">
            
                <a href="../ch5/ch5-06.html">
            
                    
                    匿名函数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.7" data-path="../ch5/ch5-07.html">
            
                <a href="../ch5/ch5-07.html">
            
                    
                    可变参数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.8" data-path="../ch5/ch5-08.html">
            
                <a href="../ch5/ch5-08.html">
            
                    
                    Deferred函数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.9" data-path="../ch5/ch5-09.html">
            
                <a href="../ch5/ch5-09.html">
            
                    
                    Panic异常
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.6.10" data-path="../ch5/ch5-10.html">
            
                <a href="../ch5/ch5-10.html">
            
                    
                    Recover捕获异常
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.7" data-path="../ch6/ch6.html">
            
                <a href="../ch6/ch6.html">
            
                    
                    方法
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.7.1" data-path="../ch6/ch6-01.html">
            
                <a href="../ch6/ch6-01.html">
            
                    
                    方法声明
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.7.2" data-path="../ch6/ch6-02.html">
            
                <a href="../ch6/ch6-02.html">
            
                    
                    基于指针对象的方法
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.7.3" data-path="../ch6/ch6-03.html">
            
                <a href="../ch6/ch6-03.html">
            
                    
                    通过嵌入结构体来扩展类型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.7.4" data-path="../ch6/ch6-04.html">
            
                <a href="../ch6/ch6-04.html">
            
                    
                    方法值和方法表达式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.7.5" data-path="../ch6/ch6-05.html">
            
                <a href="../ch6/ch6-05.html">
            
                    
                    示例: Bit数组
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.7.6" data-path="../ch6/ch6-06.html">
            
                <a href="../ch6/ch6-06.html">
            
                    
                    封装
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.8" data-path="../ch7/ch7.html">
            
                <a href="../ch7/ch7.html">
            
                    
                    接口
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.8.1" data-path="../ch7/ch7-01.html">
            
                <a href="../ch7/ch7-01.html">
            
                    
                    接口是合约
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.2" data-path="../ch7/ch7-02.html">
            
                <a href="../ch7/ch7-02.html">
            
                    
                    接口类型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.3" data-path="../ch7/ch7-03.html">
            
                <a href="../ch7/ch7-03.html">
            
                    
                    实现接口的条件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.4" data-path="../ch7/ch7-04.html">
            
                <a href="../ch7/ch7-04.html">
            
                    
                    flag.Value接口
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.5" data-path="../ch7/ch7-05.html">
            
                <a href="../ch7/ch7-05.html">
            
                    
                    接口值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.6" data-path="../ch7/ch7-06.html">
            
                <a href="../ch7/ch7-06.html">
            
                    
                    sort.Interface接口
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.7" data-path="../ch7/ch7-07.html">
            
                <a href="../ch7/ch7-07.html">
            
                    
                    http.Handler接口
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.8" data-path="../ch7/ch7-08.html">
            
                <a href="../ch7/ch7-08.html">
            
                    
                    error接口
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.9" data-path="../ch7/ch7-09.html">
            
                <a href="../ch7/ch7-09.html">
            
                    
                    示例: 表达式求值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.10" data-path="../ch7/ch7-10.html">
            
                <a href="../ch7/ch7-10.html">
            
                    
                    类型断言
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.11" data-path="../ch7/ch7-11.html">
            
                <a href="../ch7/ch7-11.html">
            
                    
                    基于类型断言识别错误类型
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.12" data-path="../ch7/ch7-12.html">
            
                <a href="../ch7/ch7-12.html">
            
                    
                    通过类型断言查询接口
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.13" data-path="../ch7/ch7-13.html">
            
                <a href="../ch7/ch7-13.html">
            
                    
                    类型分支
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.14" data-path="../ch7/ch7-14.html">
            
                <a href="../ch7/ch7-14.html">
            
                    
                    示例: 基于标记的XML解码
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.8.15" data-path="../ch7/ch7-15.html">
            
                <a href="../ch7/ch7-15.html">
            
                    
                    补充几点
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.9" data-path="ch8.html">
            
                <a href="ch8.html">
            
                    
                    Goroutines和Channels
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.9.1" data-path="ch8-01.html">
            
                <a href="ch8-01.html">
            
                    
                    Goroutines
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.2" data-path="ch8-02.html">
            
                <a href="ch8-02.html">
            
                    
                    示例: 并发的Clock服务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.3" data-path="ch8-03.html">
            
                <a href="ch8-03.html">
            
                    
                    示例: 并发的Echo服务
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.4" data-path="ch8-04.html">
            
                <a href="ch8-04.html">
            
                    
                    Channels
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.5" data-path="ch8-05.html">
            
                <a href="ch8-05.html">
            
                    
                    并发的循环
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.6" data-path="ch8-06.html">
            
                <a href="ch8-06.html">
            
                    
                    示例: 并发的Web爬虫
            
                </a>
            

            
        </li>
    
        <li class="chapter active" data-level="1.9.7" data-path="ch8-07.html">
            
                <a href="ch8-07.html">
            
                    
                    基于select的多路复用
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.8" data-path="ch8-08.html">
            
                <a href="ch8-08.html">
            
                    
                    示例: 并发的目录遍历
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.9" data-path="ch8-09.html">
            
                <a href="ch8-09.html">
            
                    
                    并发的退出
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.9.10" data-path="ch8-10.html">
            
                <a href="ch8-10.html">
            
                    
                    示例: 聊天服务
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.10" data-path="../ch9/ch9.html">
            
                <a href="../ch9/ch9.html">
            
                    
                    基于共享变量的并发
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.10.1" data-path="../ch9/ch9-01.html">
            
                <a href="../ch9/ch9-01.html">
            
                    
                    竞争条件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.2" data-path="../ch9/ch9-02.html">
            
                <a href="../ch9/ch9-02.html">
            
                    
                    sync.Mutex互斥锁
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.3" data-path="../ch9/ch9-03.html">
            
                <a href="../ch9/ch9-03.html">
            
                    
                    sync.RWMutex读写锁
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.4" data-path="../ch9/ch9-04.html">
            
                <a href="../ch9/ch9-04.html">
            
                    
                    内存同步
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.5" data-path="../ch9/ch9-05.html">
            
                <a href="../ch9/ch9-05.html">
            
                    
                    sync.Once惰性初始化
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.6" data-path="../ch9/ch9-06.html">
            
                <a href="../ch9/ch9-06.html">
            
                    
                    竞争条件检测
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.7" data-path="../ch9/ch9-07.html">
            
                <a href="../ch9/ch9-07.html">
            
                    
                    示例: 并发的非阻塞缓存
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.10.8" data-path="../ch9/ch9-08.html">
            
                <a href="../ch9/ch9-08.html">
            
                    
                    Goroutines和线程
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.11" data-path="../ch10/ch10.html">
            
                <a href="../ch10/ch10.html">
            
                    
                    包和工具
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.11.1" data-path="../ch10/ch10-01.html">
            
                <a href="../ch10/ch10-01.html">
            
                    
                    包简介
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.2" data-path="../ch10/ch10-02.html">
            
                <a href="../ch10/ch10-02.html">
            
                    
                    导入路径
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.3" data-path="../ch10/ch10-03.html">
            
                <a href="../ch10/ch10-03.html">
            
                    
                    包声明
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.4" data-path="../ch10/ch10-04.html">
            
                <a href="../ch10/ch10-04.html">
            
                    
                    导入声明
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.5" data-path="../ch10/ch10-05.html">
            
                <a href="../ch10/ch10-05.html">
            
                    
                    包的匿名导入
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.6" data-path="../ch10/ch10-06.html">
            
                <a href="../ch10/ch10-06.html">
            
                    
                    包和命名
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.11.7" data-path="../ch10/ch10-07.html">
            
                <a href="../ch10/ch10-07.html">
            
                    
                    工具
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.12" data-path="../ch11/ch11.html">
            
                <a href="../ch11/ch11.html">
            
                    
                    测试
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.12.1" data-path="../ch11/ch11-01.html">
            
                <a href="../ch11/ch11-01.html">
            
                    
                    go test
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.12.2" data-path="../ch11/ch11-02.html">
            
                <a href="../ch11/ch11-02.html">
            
                    
                    测试函数
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.12.3" data-path="../ch11/ch11-03.html">
            
                <a href="../ch11/ch11-03.html">
            
                    
                    测试覆盖率
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.12.4" data-path="../ch11/ch11-04.html">
            
                <a href="../ch11/ch11-04.html">
            
                    
                    基准测试
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.12.5" data-path="../ch11/ch11-05.html">
            
                <a href="../ch11/ch11-05.html">
            
                    
                    剖析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.12.6" data-path="../ch11/ch11-06.html">
            
                <a href="../ch11/ch11-06.html">
            
                    
                    示例函数
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.13" data-path="../ch12/ch12.html">
            
                <a href="../ch12/ch12.html">
            
                    
                    反射
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.13.1" data-path="../ch12/ch12-01.html">
            
                <a href="../ch12/ch12-01.html">
            
                    
                    为何需要反射?
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.2" data-path="../ch12/ch12-02.html">
            
                <a href="../ch12/ch12-02.html">
            
                    
                    reflect.Type和reflect.Value
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.3" data-path="../ch12/ch12-03.html">
            
                <a href="../ch12/ch12-03.html">
            
                    
                    Display递归打印
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.4" data-path="../ch12/ch12-04.html">
            
                <a href="../ch12/ch12-04.html">
            
                    
                    示例: 编码S表达式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.5" data-path="../ch12/ch12-05.html">
            
                <a href="../ch12/ch12-05.html">
            
                    
                    通过reflect.Value修改值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.6" data-path="../ch12/ch12-06.html">
            
                <a href="../ch12/ch12-06.html">
            
                    
                    示例: 解码S表达式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.7" data-path="../ch12/ch12-07.html">
            
                <a href="../ch12/ch12-07.html">
            
                    
                    获取结构体字段标签
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.8" data-path="../ch12/ch12-08.html">
            
                <a href="../ch12/ch12-08.html">
            
                    
                    显示一个类型的方法集
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.13.9" data-path="../ch12/ch12-09.html">
            
                <a href="../ch12/ch12-09.html">
            
                    
                    几点忠告
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.14" data-path="../ch13/ch13.html">
            
                <a href="../ch13/ch13.html">
            
                    
                    底层编程
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.14.1" data-path="../ch13/ch13-01.html">
            
                <a href="../ch13/ch13-01.html">
            
                    
                    unsafe.Sizeof, Alignof 和 Offsetof
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.14.2" data-path="../ch13/ch13-02.html">
            
                <a href="../ch13/ch13-02.html">
            
                    
                    unsafe.Pointer
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.14.3" data-path="../ch13/ch13-03.html">
            
                <a href="../ch13/ch13-03.html">
            
                    
                    示例: 深度相等判断
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.14.4" data-path="../ch13/ch13-04.html">
            
                <a href="../ch13/ch13-04.html">
            
                    
                    通过cgo调用C代码
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.14.5" data-path="../ch13/ch13-05.html">
            
                <a href="../ch13/ch13-05.html">
            
                    
                    几点忠告
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.15" data-path="../appendix/appendix.html">
            
                <a href="../appendix/appendix.html">
            
                    
                    附录
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.15.1" data-path="../appendix/appendix-a-errata.html">
            
                <a href="../appendix/appendix-a-errata.html">
            
                    
                    附录A：原文勘误
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.15.2" data-path="../appendix/appendix-b-author.html">
            
                <a href="../appendix/appendix-b-author.html">
            
                    
                    附录B：作者译者
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.15.3" data-path="../appendix/appendix-c-cpoyright.html">
            
                <a href="../appendix/appendix-c-cpoyright.html">
            
                    
                    附录C：译文授权
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.15.4" data-path="../appendix/appendix-d-translations.html">
            
                <a href="../appendix/appendix-d-translations.html">
            
                    
                    附录D：其它语言
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    

    <li class="divider"></li>

    <li>
        <a href="https://www.gitbook.com" target="blank" class="gitbook-link">
            本书使用 GitBook 发布
        </a>
    </li>
</ul>


                </nav>
            
        
    </div>

    <div class="book-body">
        
            <div class="body-inner">
                
                    

<div class="book-header" role="navigation">
    

    <!-- Title -->
    <h1>
        <i class="fa fa-circle-o-notch fa-spin"></i>
        <a href=".." >基于select的多路复用</a>
    </h1>
</div>




                    <div class="page-wrapper" tabindex="-1" role="main">
                        <div class="page-inner">
                            
                                <section class="normal markdown-section">
                                
                                <h2 id="87-&#x57FA;&#x4E8E;select&#x7684;&#x591A;&#x8DEF;&#x590D;&#x7528;">8.7. &#x57FA;&#x4E8E;select&#x7684;&#x591A;&#x8DEF;&#x590D;&#x7528;</h2>
<p>&#x4E0B;&#x9762;&#x7684;&#x7A0B;&#x5E8F;&#x4F1A;&#x8FDB;&#x884C;&#x706B;&#x7BAD;&#x53D1;&#x5C04;&#x7684;&#x5012;&#x8BA1;&#x65F6;&#x3002;time.Tick&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;channel&#xFF0C;&#x7A0B;&#x5E8F;&#x4F1A;&#x5468;&#x671F;&#x6027;&#x5730;&#x50CF;&#x4E00;&#x4E2A;&#x8282;&#x62CD;&#x5668;&#x4E00;&#x6837;&#x5411;&#x8FD9;&#x4E2A;channel&#x53D1;&#x9001;&#x4E8B;&#x4EF6;&#x3002;&#x6BCF;&#x4E00;&#x4E2A;&#x4E8B;&#x4EF6;&#x7684;&#x503C;&#x662F;&#x4E00;&#x4E2A;&#x65F6;&#x95F4;&#x6233;&#xFF0C;&#x4E0D;&#x8FC7;&#x66F4;&#x6709;&#x610F;&#x601D;&#x7684;&#x662F;&#x5176;&#x4F20;&#x9001;&#x65B9;&#x5F0F;&#x3002;</p>
<p><u><i>gopl.io/ch8/countdown1</i></u></p>
<pre><code class="lang-go"><span class="hljs-keyword">func</span> main() {
    fmt.Println(<span class="hljs-string">&quot;Commencing countdown.&quot;</span>)
    tick := time.Tick(<span class="hljs-number">1</span> * time.Second)
    <span class="hljs-keyword">for</span> countdown := <span class="hljs-number">10</span>; countdown &gt; <span class="hljs-number">0</span>; countdown-- {
        fmt.Println(countdown)
        &lt;-tick
    }
    launch()
}
</code></pre>
<p>&#x73B0;&#x5728;&#x6211;&#x4EEC;&#x8BA9;&#x8FD9;&#x4E2A;&#x7A0B;&#x5E8F;&#x652F;&#x6301;&#x5728;&#x5012;&#x8BA1;&#x65F6;&#x4E2D;&#xFF0C;&#x7528;&#x6237;&#x6309;&#x4E0B;return&#x952E;&#x65F6;&#x76F4;&#x63A5;&#x4E2D;&#x65AD;&#x53D1;&#x5C04;&#x6D41;&#x7A0B;&#x3002;&#x9996;&#x5148;&#xFF0C;&#x6211;&#x4EEC;&#x542F;&#x52A8;&#x4E00;&#x4E2A;goroutine&#xFF0C;&#x8FD9;&#x4E2A;goroutine&#x4F1A;&#x5C1D;&#x8BD5;&#x4ECE;&#x6807;&#x51C6;&#x8F93;&#x5165;&#x4E2D;&#x8BFB;&#x5165;&#x4E00;&#x4E2A;&#x5355;&#x72EC;&#x7684;byte&#x5E76;&#x4E14;&#xFF0C;&#x5982;&#x679C;&#x6210;&#x529F;&#x4E86;&#xFF0C;&#x4F1A;&#x5411;&#x540D;&#x4E3A;abort&#x7684;channel&#x53D1;&#x9001;&#x4E00;&#x4E2A;&#x503C;&#x3002;</p>
<p><u><i>gopl.io/ch8/countdown2</i></u></p>
<pre><code class="lang-go">abort := <span class="hljs-built_in">make</span>(<span class="hljs-keyword">chan</span> <span class="hljs-keyword">struct</span>{})
<span class="hljs-keyword">go</span> <span class="hljs-keyword">func</span>() {
    os.Stdin.Read(<span class="hljs-built_in">make</span>([]<span class="hljs-keyword">byte</span>, <span class="hljs-number">1</span>)) <span class="hljs-comment">// read a single byte</span>
    abort &lt;- <span class="hljs-keyword">struct</span>{}{}
}()
</code></pre>
<p>&#x73B0;&#x5728;&#x6BCF;&#x4E00;&#x6B21;&#x8BA1;&#x6570;&#x5FAA;&#x73AF;&#x7684;&#x8FED;&#x4EE3;&#x90FD;&#x9700;&#x8981;&#x7B49;&#x5F85;&#x4E24;&#x4E2A;channel&#x4E2D;&#x7684;&#x5176;&#x4E2D;&#x4E00;&#x4E2A;&#x8FD4;&#x56DE;&#x4E8B;&#x4EF6;&#x4E86;&#xFF1A;&#x5F53;&#x4E00;&#x5207;&#x6B63;&#x5E38;&#x65F6;&#x7684;ticker channel&#xFF08;&#x5C31;&#x50CF;NASA jorgon&#x7684;&quot;nominal&quot;&#xFF0C;&#x8BD1;&#x6CE8;&#xFF1A;&#x8FD9;&#x6897;&#x4F30;&#x8BA1;&#x6211;&#x4EEC;&#x662F;&#x4E0D;&#x61C2;&#x4E86;&#xFF09;&#x6216;&#x8005;&#x5F02;&#x5E38;&#x65F6;&#x8FD4;&#x56DE;&#x7684;abort&#x4E8B;&#x4EF6;&#x3002;&#x6211;&#x4EEC;&#x65E0;&#x6CD5;&#x505A;&#x5230;&#x4ECE;&#x6BCF;&#x4E00;&#x4E2A;channel&#x4E2D;&#x63A5;&#x6536;&#x4FE1;&#x606F;&#xFF0C;&#x5982;&#x679C;&#x6211;&#x4EEC;&#x8FD9;&#x4E48;&#x505A;&#x7684;&#x8BDD;&#xFF0C;&#x5982;&#x679C;&#x7B2C;&#x4E00;&#x4E2A;channel&#x4E2D;&#x6CA1;&#x6709;&#x4E8B;&#x4EF6;&#x53D1;&#x8FC7;&#x6765;&#x90A3;&#x4E48;&#x7A0B;&#x5E8F;&#x5C31;&#x4F1A;&#x7ACB;&#x523B;&#x88AB;&#x963B;&#x585E;&#xFF0C;&#x8FD9;&#x6837;&#x6211;&#x4EEC;&#x5C31;&#x65E0;&#x6CD5;&#x6536;&#x5230;&#x7B2C;&#x4E8C;&#x4E2A;channel&#x4E2D;&#x53D1;&#x8FC7;&#x6765;&#x7684;&#x4E8B;&#x4EF6;&#x3002;&#x8FD9;&#x65F6;&#x5019;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x591A;&#x8DEF;&#x590D;&#x7528;&#xFF08;multiplex&#xFF09;&#x8FD9;&#x4E9B;&#x64CD;&#x4F5C;&#x4E86;&#xFF0C;&#x4E3A;&#x4E86;&#x80FD;&#x591F;&#x591A;&#x8DEF;&#x590D;&#x7528;&#xFF0C;&#x6211;&#x4EEC;&#x4F7F;&#x7528;&#x4E86;select&#x8BED;&#x53E5;&#x3002;</p>
<pre><code class="lang-go"><span class="hljs-keyword">select</span> {
<span class="hljs-keyword">case</span> &lt;-ch1:
    <span class="hljs-comment">// ...</span>
<span class="hljs-keyword">case</span> x := &lt;-ch2:
    <span class="hljs-comment">// ...use x...</span>
<span class="hljs-keyword">case</span> ch3 &lt;- y:
    <span class="hljs-comment">// ...</span>
<span class="hljs-keyword">default</span>:
    <span class="hljs-comment">// ...</span>
}
</code></pre>
<p>&#x4E0A;&#x9762;&#x662F;select&#x8BED;&#x53E5;&#x7684;&#x4E00;&#x822C;&#x5F62;&#x5F0F;&#x3002;&#x548C;switch&#x8BED;&#x53E5;&#x7A0D;&#x5FAE;&#x6709;&#x70B9;&#x76F8;&#x4F3C;&#xFF0C;&#x4E5F;&#x4F1A;&#x6709;&#x51E0;&#x4E2A;case&#x548C;&#x6700;&#x540E;&#x7684;default&#x9009;&#x62E9;&#x5206;&#x652F;&#x3002;&#x6BCF;&#x4E00;&#x4E2A;case&#x4EE3;&#x8868;&#x4E00;&#x4E2A;&#x901A;&#x4FE1;&#x64CD;&#x4F5C;&#xFF08;&#x5728;&#x67D0;&#x4E2A;channel&#x4E0A;&#x8FDB;&#x884C;&#x53D1;&#x9001;&#x6216;&#x8005;&#x63A5;&#x6536;&#xFF09;&#xFF0C;&#x5E76;&#x4E14;&#x4F1A;&#x5305;&#x542B;&#x4E00;&#x4E9B;&#x8BED;&#x53E5;&#x7EC4;&#x6210;&#x7684;&#x4E00;&#x4E2A;&#x8BED;&#x53E5;&#x5757;&#x3002;&#x4E00;&#x4E2A;&#x63A5;&#x6536;&#x8868;&#x8FBE;&#x5F0F;&#x53EF;&#x80FD;&#x53EA;&#x5305;&#x542B;&#x63A5;&#x6536;&#x8868;&#x8FBE;&#x5F0F;&#x81EA;&#x8EAB;&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x4E0D;&#x628A;&#x63A5;&#x6536;&#x5230;&#x7684;&#x503C;&#x8D4B;&#x503C;&#x7ED9;&#x53D8;&#x91CF;&#x4EC0;&#x4E48;&#x7684;&#xFF09;&#xFF0C;&#x5C31;&#x50CF;&#x4E0A;&#x9762;&#x7684;&#x7B2C;&#x4E00;&#x4E2A;case&#xFF0C;&#x6216;&#x8005;&#x5305;&#x542B;&#x5728;&#x4E00;&#x4E2A;&#x7B80;&#x77ED;&#x7684;&#x53D8;&#x91CF;&#x58F0;&#x660E;&#x4E2D;&#xFF0C;&#x50CF;&#x7B2C;&#x4E8C;&#x4E2A;case&#x91CC;&#x4E00;&#x6837;&#xFF1B;&#x7B2C;&#x4E8C;&#x79CD;&#x5F62;&#x5F0F;&#x8BA9;&#x4F60;&#x80FD;&#x591F;&#x5F15;&#x7528;&#x63A5;&#x6536;&#x5230;&#x7684;&#x503C;&#x3002;</p>
<p>select&#x4F1A;&#x7B49;&#x5F85;case&#x4E2D;&#x6709;&#x80FD;&#x591F;&#x6267;&#x884C;&#x7684;case&#x65F6;&#x53BB;&#x6267;&#x884C;&#x3002;&#x5F53;&#x6761;&#x4EF6;&#x6EE1;&#x8DB3;&#x65F6;&#xFF0C;select&#x624D;&#x4F1A;&#x53BB;&#x901A;&#x4FE1;&#x5E76;&#x6267;&#x884C;case&#x4E4B;&#x540E;&#x7684;&#x8BED;&#x53E5;&#xFF1B;&#x8FD9;&#x65F6;&#x5019;&#x5176;&#x5B83;&#x901A;&#x4FE1;&#x662F;&#x4E0D;&#x4F1A;&#x6267;&#x884C;&#x7684;&#x3002;&#x4E00;&#x4E2A;&#x6CA1;&#x6709;&#x4EFB;&#x4F55;case&#x7684;select&#x8BED;&#x53E5;&#x5199;&#x4F5C;select{}&#xFF0C;&#x4F1A;&#x6C38;&#x8FDC;&#x5730;&#x7B49;&#x5F85;&#x4E0B;&#x53BB;&#x3002;</p>
<p>&#x8BA9;&#x6211;&#x4EEC;&#x56DE;&#x5230;&#x6211;&#x4EEC;&#x7684;&#x706B;&#x7BAD;&#x53D1;&#x5C04;&#x7A0B;&#x5E8F;&#x3002;time.After&#x51FD;&#x6570;&#x4F1A;&#x7ACB;&#x5373;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;channel&#xFF0C;&#x5E76;&#x8D77;&#x4E00;&#x4E2A;&#x65B0;&#x7684;goroutine&#x5728;&#x7ECF;&#x8FC7;&#x7279;&#x5B9A;&#x7684;&#x65F6;&#x95F4;&#x540E;&#x5411;&#x8BE5;channel&#x53D1;&#x9001;&#x4E00;&#x4E2A;&#x72EC;&#x7ACB;&#x7684;&#x503C;&#x3002;&#x4E0B;&#x9762;&#x7684;select&#x8BED;&#x53E5;&#x4F1A;&#x4E00;&#x76F4;&#x7B49;&#x5F85;&#x76F4;&#x5230;&#x4E24;&#x4E2A;&#x4E8B;&#x4EF6;&#x4E2D;&#x7684;&#x4E00;&#x4E2A;&#x5230;&#x8FBE;&#xFF0C;&#x65E0;&#x8BBA;&#x662F;abort&#x4E8B;&#x4EF6;&#x6216;&#x8005;&#x4E00;&#x4E2A;10&#x79D2;&#x7ECF;&#x8FC7;&#x7684;&#x4E8B;&#x4EF6;&#x3002;&#x5982;&#x679C;10&#x79D2;&#x7ECF;&#x8FC7;&#x4E86;&#x8FD8;&#x6CA1;&#x6709;abort&#x4E8B;&#x4EF6;&#x8FDB;&#x5165;&#xFF0C;&#x90A3;&#x4E48;&#x706B;&#x7BAD;&#x5C31;&#x4F1A;&#x53D1;&#x5C04;&#x3002;</p>
<pre><code class="lang-go"><span class="hljs-keyword">func</span> main() {
    <span class="hljs-comment">// ...create abort channel...</span>

    fmt.Println(<span class="hljs-string">&quot;Commencing countdown.  Press return to abort.&quot;</span>)
    <span class="hljs-keyword">select</span> {
    <span class="hljs-keyword">case</span> &lt;-time.After(<span class="hljs-number">10</span> * time.Second):
        <span class="hljs-comment">// Do nothing.</span>
    <span class="hljs-keyword">case</span> &lt;-abort:
        fmt.Println(<span class="hljs-string">&quot;Launch aborted!&quot;</span>)
        <span class="hljs-keyword">return</span>
    }
    launch()
}
</code></pre>
<p>&#x4E0B;&#x9762;&#x8FD9;&#x4E2A;&#x4F8B;&#x5B50;&#x66F4;&#x5FAE;&#x5999;&#x3002;ch&#x8FD9;&#x4E2A;channel&#x7684;buffer&#x5927;&#x5C0F;&#x662F;1&#xFF0C;&#x6240;&#x4EE5;&#x4F1A;&#x4EA4;&#x66FF;&#x7684;&#x4E3A;&#x7A7A;&#x6216;&#x4E3A;&#x6EE1;&#xFF0C;&#x6240;&#x4EE5;&#x53EA;&#x6709;&#x4E00;&#x4E2A;case&#x53EF;&#x4EE5;&#x8FDB;&#x884C;&#x4E0B;&#x53BB;&#xFF0C;&#x65E0;&#x8BBA;i&#x662F;&#x5947;&#x6570;&#x6216;&#x8005;&#x5076;&#x6570;&#xFF0C;&#x5B83;&#x90FD;&#x4F1A;&#x6253;&#x5370;0 2 4 6 8&#x3002;</p>
<pre><code class="lang-go">ch := <span class="hljs-built_in">make</span>(<span class="hljs-keyword">chan</span> <span class="hljs-keyword">int</span>, <span class="hljs-number">1</span>)
<span class="hljs-keyword">for</span> i := <span class="hljs-number">0</span>; i &lt; <span class="hljs-number">10</span>; i++ {
    <span class="hljs-keyword">select</span> {
    <span class="hljs-keyword">case</span> x := &lt;-ch:
        fmt.Println(x) <span class="hljs-comment">// &quot;0&quot; &quot;2&quot; &quot;4&quot; &quot;6&quot; &quot;8&quot;</span>
    <span class="hljs-keyword">case</span> ch &lt;- i:
    }
}
</code></pre>
<p>&#x5982;&#x679C;&#x591A;&#x4E2A;case&#x540C;&#x65F6;&#x5C31;&#x7EEA;&#x65F6;&#xFF0C;select&#x4F1A;&#x968F;&#x673A;&#x5730;&#x9009;&#x62E9;&#x4E00;&#x4E2A;&#x6267;&#x884C;&#xFF0C;&#x8FD9;&#x6837;&#x6765;&#x4FDD;&#x8BC1;&#x6BCF;&#x4E00;&#x4E2A;channel&#x90FD;&#x6709;&#x5E73;&#x7B49;&#x7684;&#x88AB;select&#x7684;&#x673A;&#x4F1A;&#x3002;&#x589E;&#x52A0;&#x524D;&#x4E00;&#x4E2A;&#x4F8B;&#x5B50;&#x7684;buffer&#x5927;&#x5C0F;&#x4F1A;&#x4F7F;&#x5176;&#x8F93;&#x51FA;&#x53D8;&#x5F97;&#x4E0D;&#x786E;&#x5B9A;&#xFF0C;&#x56E0;&#x4E3A;&#x5F53;buffer&#x65E2;&#x4E0D;&#x4E3A;&#x6EE1;&#x4E5F;&#x4E0D;&#x4E3A;&#x7A7A;&#x65F6;&#xFF0C;select&#x8BED;&#x53E5;&#x7684;&#x6267;&#x884C;&#x60C5;&#x51B5;&#x5C31;&#x50CF;&#x662F;&#x629B;&#x786C;&#x5E01;&#x7684;&#x884C;&#x4E3A;&#x4E00;&#x6837;&#x662F;&#x968F;&#x673A;&#x7684;&#x3002;</p>
<p>&#x4E0B;&#x9762;&#x8BA9;&#x6211;&#x4EEC;&#x7684;&#x53D1;&#x5C04;&#x7A0B;&#x5E8F;&#x6253;&#x5370;&#x5012;&#x8BA1;&#x65F6;&#x3002;&#x8FD9;&#x91CC;&#x7684;select&#x8BED;&#x53E5;&#x4F1A;&#x4F7F;&#x6BCF;&#x6B21;&#x5FAA;&#x73AF;&#x8FED;&#x4EE3;&#x7B49;&#x5F85;&#x4E00;&#x79D2;&#x6765;&#x6267;&#x884C;&#x9000;&#x51FA;&#x64CD;&#x4F5C;&#x3002;</p>
<p><u><i>gopl.io/ch8/countdown3</i></u></p>
<pre><code class="lang-go"><span class="hljs-keyword">func</span> main() {
    <span class="hljs-comment">// ...create abort channel...</span>

    fmt.Println(<span class="hljs-string">&quot;Commencing countdown.  Press return to abort.&quot;</span>)
    tick := time.Tick(<span class="hljs-number">1</span> * time.Second)
    <span class="hljs-keyword">for</span> countdown := <span class="hljs-number">10</span>; countdown &gt; <span class="hljs-number">0</span>; countdown-- {
        fmt.Println(countdown)
        <span class="hljs-keyword">select</span> {
        <span class="hljs-keyword">case</span> &lt;-tick:
            <span class="hljs-comment">// Do nothing.</span>
        <span class="hljs-keyword">case</span> &lt;-abort:
            fmt.Println(<span class="hljs-string">&quot;Launch aborted!&quot;</span>)
            <span class="hljs-keyword">return</span>
        }
    }
    launch()
}
</code></pre>
<p>time.Tick&#x51FD;&#x6570;&#x8868;&#x73B0;&#x5F97;&#x597D;&#x50CF;&#x5B83;&#x521B;&#x5EFA;&#x4E86;&#x4E00;&#x4E2A;&#x5728;&#x5FAA;&#x73AF;&#x4E2D;&#x8C03;&#x7528;time.Sleep&#x7684;goroutine&#xFF0C;&#x6BCF;&#x6B21;&#x88AB;&#x5524;&#x9192;&#x65F6;&#x53D1;&#x9001;&#x4E00;&#x4E2A;&#x4E8B;&#x4EF6;&#x3002;&#x5F53;countdown&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x65F6;&#xFF0C;&#x5B83;&#x4F1A;&#x505C;&#x6B62;&#x4ECE;tick&#x4E2D;&#x63A5;&#x6536;&#x4E8B;&#x4EF6;&#xFF0C;&#x4F46;&#x662F;ticker&#x8FD9;&#x4E2A;goroutine&#x8FD8;&#x4F9D;&#x7136;&#x5B58;&#x6D3B;&#xFF0C;&#x7EE7;&#x7EED;&#x5F92;&#x52B3;&#x5730;&#x5C1D;&#x8BD5;&#x5411;channel&#x4E2D;&#x53D1;&#x9001;&#x503C;&#xFF0C;&#x7136;&#x800C;&#x8FD9;&#x65F6;&#x5019;&#x5DF2;&#x7ECF;&#x6CA1;&#x6709;&#x5176;&#x5B83;&#x7684;goroutine&#x4F1A;&#x4ECE;&#x8BE5;channel&#x4E2D;&#x63A5;&#x6536;&#x503C;&#x4E86;&#x2014;&#x2014;&#x8FD9;&#x88AB;&#x79F0;&#x4E3A;goroutine&#x6CC4;&#x9732;&#xFF08;&#xA7;8.4.4&#xFF09;&#x3002;</p>
<p>Tick&#x51FD;&#x6570;&#x633A;&#x65B9;&#x4FBF;&#xFF0C;&#x4F46;&#x662F;&#x53EA;&#x6709;&#x5F53;&#x7A0B;&#x5E8F;&#x6574;&#x4E2A;&#x751F;&#x547D;&#x5468;&#x671F;&#x90FD;&#x9700;&#x8981;&#x8FD9;&#x4E2A;&#x65F6;&#x95F4;&#x65F6;&#x6211;&#x4EEC;&#x4F7F;&#x7528;&#x5B83;&#x624D;&#x6BD4;&#x8F83;&#x5408;&#x9002;&#x3002;&#x5426;&#x5219;&#x7684;&#x8BDD;&#xFF0C;&#x6211;&#x4EEC;&#x5E94;&#x8BE5;&#x4F7F;&#x7528;&#x4E0B;&#x9762;&#x7684;&#x8FD9;&#x79CD;&#x6A21;&#x5F0F;&#xFF1A;</p>
<pre><code class="lang-go">ticker := time.NewTicker(<span class="hljs-number">1</span> * time.Second)
&lt;-ticker.C    <span class="hljs-comment">// receive from the ticker&apos;s channel</span>
ticker.Stop() <span class="hljs-comment">// cause the ticker&apos;s goroutine to terminate</span>
</code></pre>
<p>&#x6709;&#x65F6;&#x5019;&#x6211;&#x4EEC;&#x5E0C;&#x671B;&#x80FD;&#x591F;&#x4ECE;channel&#x4E2D;&#x53D1;&#x9001;&#x6216;&#x8005;&#x63A5;&#x6536;&#x503C;&#xFF0C;&#x5E76;&#x907F;&#x514D;&#x56E0;&#x4E3A;&#x53D1;&#x9001;&#x6216;&#x8005;&#x63A5;&#x6536;&#x5BFC;&#x81F4;&#x7684;&#x963B;&#x585E;&#xFF0C;&#x5C24;&#x5176;&#x662F;&#x5F53;channel&#x6CA1;&#x6709;&#x51C6;&#x5907;&#x597D;&#x5199;&#x6216;&#x8005;&#x8BFB;&#x65F6;&#x3002;select&#x8BED;&#x53E5;&#x5C31;&#x53EF;&#x4EE5;&#x5B9E;&#x73B0;&#x8FD9;&#x6837;&#x7684;&#x529F;&#x80FD;&#x3002;select&#x4F1A;&#x6709;&#x4E00;&#x4E2A;default&#x6765;&#x8BBE;&#x7F6E;&#x5F53;&#x5176;&#x5B83;&#x7684;&#x64CD;&#x4F5C;&#x90FD;&#x4E0D;&#x80FD;&#x591F;&#x9A6C;&#x4E0A;&#x88AB;&#x5904;&#x7406;&#x65F6;&#x7A0B;&#x5E8F;&#x9700;&#x8981;&#x6267;&#x884C;&#x54EA;&#x4E9B;&#x903B;&#x8F91;&#x3002;</p>
<p>&#x4E0B;&#x9762;&#x7684;select&#x8BED;&#x53E5;&#x4F1A;&#x5728;abort channel&#x4E2D;&#x6709;&#x503C;&#x65F6;&#xFF0C;&#x4ECE;&#x5176;&#x4E2D;&#x63A5;&#x6536;&#x503C;&#xFF1B;&#x65E0;&#x503C;&#x65F6;&#x4EC0;&#x4E48;&#x90FD;&#x4E0D;&#x505A;&#x3002;&#x8FD9;&#x662F;&#x4E00;&#x4E2A;&#x975E;&#x963B;&#x585E;&#x7684;&#x63A5;&#x6536;&#x64CD;&#x4F5C;&#xFF1B;&#x53CD;&#x590D;&#x5730;&#x505A;&#x8FD9;&#x6837;&#x7684;&#x64CD;&#x4F5C;&#x53EB;&#x505A;&#x201C;&#x8F6E;&#x8BE2;channel&#x201D;&#x3002;</p>
<pre><code class="lang-go"><span class="hljs-keyword">select</span> {
<span class="hljs-keyword">case</span> &lt;-abort:
    fmt.Printf(<span class="hljs-string">&quot;Launch aborted!\n&quot;</span>)
    <span class="hljs-keyword">return</span>
<span class="hljs-keyword">default</span>:
    <span class="hljs-comment">// do nothing</span>
}
</code></pre>
<p>channel&#x7684;&#x96F6;&#x503C;&#x662F;nil&#x3002;&#x4E5F;&#x8BB8;&#x4F1A;&#x8BA9;&#x4F60;&#x89C9;&#x5F97;&#x6BD4;&#x8F83;&#x5947;&#x602A;&#xFF0C;nil&#x7684;channel&#x6709;&#x65F6;&#x5019;&#x4E5F;&#x662F;&#x6709;&#x4E00;&#x4E9B;&#x7528;&#x5904;&#x7684;&#x3002;&#x56E0;&#x4E3A;&#x5BF9;&#x4E00;&#x4E2A;nil&#x7684;channel&#x53D1;&#x9001;&#x548C;&#x63A5;&#x6536;&#x64CD;&#x4F5C;&#x4F1A;&#x6C38;&#x8FDC;&#x963B;&#x585E;&#xFF0C;&#x5728;select&#x8BED;&#x53E5;&#x4E2D;&#x64CD;&#x4F5C;nil&#x7684;channel&#x6C38;&#x8FDC;&#x90FD;&#x4E0D;&#x4F1A;&#x88AB;select&#x5230;&#x3002;</p>
<p>&#x8FD9;&#x4F7F;&#x5F97;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x7528;nil&#x6765;&#x6FC0;&#x6D3B;&#x6216;&#x8005;&#x7981;&#x7528;case&#xFF0C;&#x6765;&#x8FBE;&#x6210;&#x5904;&#x7406;&#x5176;&#x5B83;&#x8F93;&#x5165;&#x6216;&#x8F93;&#x51FA;&#x4E8B;&#x4EF6;&#x65F6;&#x8D85;&#x65F6;&#x548C;&#x53D6;&#x6D88;&#x7684;&#x903B;&#x8F91;&#x3002;&#x6211;&#x4EEC;&#x4F1A;&#x5728;&#x4E0B;&#x4E00;&#x8282;&#x4E2D;&#x770B;&#x5230;&#x4E00;&#x4E2A;&#x4F8B;&#x5B50;&#x3002;</p>
<p><strong>&#x7EC3;&#x4E60; 8.8&#xFF1A;</strong> &#x4F7F;&#x7528;select&#x6765;&#x6539;&#x9020;8.3&#x8282;&#x4E2D;&#x7684;echo&#x670D;&#x52A1;&#x5668;&#xFF0C;&#x4E3A;&#x5176;&#x589E;&#x52A0;&#x8D85;&#x65F6;&#xFF0C;&#x8FD9;&#x6837;&#x670D;&#x52A1;&#x5668;&#x53EF;&#x4EE5;&#x5728;&#x5BA2;&#x6237;&#x7AEF;10&#x79D2;&#x4E2D;&#x6CA1;&#x6709;&#x4EFB;&#x4F55;&#x558A;&#x8BDD;&#x65F6;&#x81EA;&#x52A8;&#x65AD;&#x5F00;&#x8FDE;&#x63A5;&#x3002;</p>

                                
                                </section>
                            
                        </div>
                    </div>
                
            </div>

            
                
                <a href="ch8-06.html" class="navigation navigation-prev " aria-label="Previous page: 示例: 并发的Web爬虫">
                    <i class="fa fa-angle-left"></i>
                </a>
                
                
                <a href="ch8-08.html" class="navigation navigation-next " aria-label="Next page: 示例: 并发的目录遍历">
                    <i class="fa fa-angle-right"></i>
                </a>
                
            
        
    </div>

    <script>
        var gitbook = gitbook || [];
        gitbook.push(function() {
            gitbook.page.hasChanged({"page":{"title":"基于select的多路复用","level":"1.9.7","depth":2,"next":{"title":"示例: 并发的目录遍历","level":"1.9.8","depth":2,"path":"ch8/ch8-08.md","ref":"ch8/ch8-08.md","articles":[]},"previous":{"title":"示例: 并发的Web爬虫","level":"1.9.6","depth":2,"path":"ch8/ch8-06.md","ref":"ch8/ch8-06.md","articles":[]},"dir":"ltr"},"config":{"plugins":["katex","-search","-lunr"],"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"pluginsConfig":{"katex":{},"highlight":{},"sharing":{"facebook":true,"twitter":true,"google":false,"weibo":false,"instapaper":false,"vk":false,"all":["facebook","google","twitter","weibo","instapaper"]},"fontsettings":{"theme":"white","family":"sans","size":2},"theme-default":{"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"showLevel":false}},"theme":"default","pdf":{"pageNumbers":true,"fontSize":12,"fontFamily":"Arial","paperSize":"a4","chapterMark":"pagebreak","pageBreaksBefore":"/","margin":{"right":62,"left":62,"top":56,"bottom":56}},"structure":{"langs":"LANGS.md","readme":"preface.md","glossary":"GLOSSARY.md","summary":"SUMMARY.md"},"variables":{},"title":"Go语言圣经","language":"zh-hans","gitbook":"3.x","description":"<The Go Programming Language>中文版"},"file":{"path":"ch8/ch8-07.md","mtime":"2020-08-13T07:15:34.337Z","type":"markdown"},"gitbook":{"version":"3.2.3","time":"2020-08-13T07:17:23.922Z"},"basePath":"..","book":{"language":""}});
        });
    </script>
</div>

        
    <script src="../gitbook/gitbook.js"></script>
    <script src="../gitbook/theme.js"></script>
    
        
        <script src="../gitbook/gitbook-plugin-sharing/buttons.js"></script>
        
    
        
        <script src="../gitbook/gitbook-plugin-fontsettings/fontsettings.js"></script>
        
    

    </body>
</html>

